I'm on the phone with them now...I had to wait on hold for about 10 minutes.
I finally got through to someone, and he was definite: Anyone who purchased a Rio car within 30 days of the price drop WILL get a refund, but you have to call and ask for it (be sure to get a case number).
Their database is down right now, so they're doing things manually.
He also stated that those "charges" everyone is seeing for the units they ordered are simply from the approval process, which is normal. When you place an order, the company verifies the credit information, and "reserves" the amount of the order. But it is not deducted from your balance (i.e., "charged") until the order ships.
He further verified that there is a 10GB unit reserved for me as part of my 2nd order, so while they're swamped with orders, those who purchased early should get the unit(s) they ordered (I placed mine the morning of 12/22.)